Orthopoxvirus inclusion bodies

Orthopoxvirus inclusion bodies are aggregates of stable protein produced by poxvirus virions in the cell nuclei and/or cytoplasm of epithelial cells in humans. They are important as sites of viral replication.^[1][2]

Morphology

Morphologically, there are two types of Orthopoxvirus inclusion bodies: Type-A inclusion bodies and Guarnnier bodies. Type-A inclusion bodies are found only in certain poxviruses like cowpox.^[3] Guarnnier bodies are found in all poxvirus infections and their presence is diagnostic.^[4] The diagnosis of an orthopoxvirus infection can also be made rapidly by electron microscopic examination of pustular fluid or scabs. However, all orthopoxviruses exhibit identical brick-shaped virions by electron microscopy.^{[citation needed]}

Guarnieri bodies are named for Giuseppe Guarnieri (1856–1918), an Italian physician who first described them.^[5]